Keywords

1 Introduction

There are many kinds of research available on the design of mobile applications from many years, design guidelines are still producing difficulties and challenges for VIP. A VIP use these mobile applications to fulfill their needs with some help. Designing mobile applications for VIP involves specific challenges that are different from the designer of a mobile application. These challenges are expectations, experience, needs, and environment in which VIP use mobile applications. Mobile applications should be planned to developed according to the needs and continuous collaborations with VIP. The development of mobile applications is growing faster and its use becomes more widely due to its independence, in order to access the information and new technologies for visually impaired people(VIP). For VIP there are many organizations and individuals have tried to develop the mobile application accessibility instructions. The latest report by the World Health Organization [1] on dated 18 Oct 2018, there were about 1.3 billion people have lived with some visual impairment. This is a large portion of the total population but this portion remains cut off from new mobile development and research design technology. There is proof that VIP [2, 3] faced many problems while using mobile applications. There were many types of research that have explored the wishes and requirements of VIP with respect to the requirements of mobile phone applications. In this exploration, they found the multi-functional abilities that are not available in old mobile phone applications. From practical research especially on the accessibility of mobile phone user interface design guidelines for VIP, there is no extensive contract. For VIP, global designing access should be allowed in mobile application designing. The people’s quality of life has changed due to the appearance of mobile applications. The people can enjoy social network services, online shopping, mobile group chats, and email reading like services through these mobile applications. However, the visual interface is very prominent in all these mobile applications, therefore VIP has difficulties to access these mobile applications.

According to a survey on the accessibility of information systems [4], there is a need for extraordinary enhancement in the accessibility of mobile applications for VIP. In order to make progress the usability and accessibility problems in mobile applications, the usability guidelines provide by mobile phone companies like Google, Apple, and Samsung. There is deep darkness on the availability of these guidelines with respect to developers and designers due to that they are not aware of these rules and regulations. There are no international guidelines and standards for accessibility of a mobile application for VIP, such as Web Content Accessibility Guidelines(WCAG)[5]. The work done in the past for VIP is mainly focus on the graphical interfaces of mobile applications, and there are no implemented features in mobile applications for VIP. This study evaluates the accessibility and consequence of mobile applications on VIP and comparison the use of mobile applications by them. The main goal of this study explores the difficulties faced by VIP during the use of the mobile application in which the usability of different mobile applications from VIP’s perspective was evaluated.

The remaining part of this paper is organized as follows. Section 2 describes the background and literature review. Section 3 describes the methodology of the experiment. VIP’s interaction with original mobile applicatios in Sect. 4. Designing a new prototype of mobile application in Sect. 5.The Results and Discussion are described in Sect. 6. The conclusion and feature direction are described in Sect. 7.

2 Background and Literature Review

VIP are faced with difficulties in order to obtain their specific results while using mobile applications. They take a longer time to complete their tasks, performance to complete a task is also slow [10]. The PACMAD (People At the Centre of Mobile Application Development) is proposed by Harrison et al. [7] in which they described that mobile environments do not follow the usability standards. They also insist that effectiveness, efficiency, and satisfaction should be included to measure the usability of mobile applications. There was a vast investigation upon the mobile application design domain for VIP by researchers. In order to improve accessibility and interaction between touch-screen based smartphones and VIP, an investigation analyzed by Chiti et al [6] in 2012. An idea of a low vision mobile application portal was proposed for the development method by Sanchez et al [8]. VIP can gain access with the help of the developer’s designed API to a, particularly designed mobile application accessibility feature. In modern software design, many kinds of research have communicated the major feature of mobile application development with user-centered design principles [11, 12]. In order to provide self-reliance, privacy, and real-world metaphor research presented the guidelines that can be used to evolve accessible mobile devices for VIP [9]. However, in the real process of developing these guidelines are very common. Kane et al. [10] in an account for better use of touchscreen-based gestures manage a study in which they compared that how sighted people and VIP use the touch screen gestures. They proposed the design guidelines for accessible touch screen mobile applications that are mainly focused on gestures such as flick, multitouch, symbol, and shapes. Accessibility guidelines and standards of mobile applications promote and develop by an organization Web Accessibility Initiative (WAI) associated with World Wide Web Consortium (W3C). Mobile Web Accessibility Guideline (MWAG) 2.0 is proposed by WAI. There are four criteria of mobile environment guidelines depends on Mobile Web Accessibility Guideline (MWAG) 2.0 like operable, understandable, namely perceivable, and robust [5]. However, these guidelines are not particularly for mobile applications but somehow these guidelines are used for sorting out the accessibility problems in mobile webpages. iOS is provided a gesture-based screen reader is called VoiceOver [13]. VIP is able to navigate and type text input with the help of VoiceOver. VIP can adjust the focus of an object by moving the cursor position up, down, right, and left. The focuses object’s description and name listen by the VoiceOver. When a user touches the character on a keyboard for input, VoiceOver pronounces that characters. In iOS VoiceOver handles both third-party integrated applications and built-in applications. Online mobile applications have pointed out that VIP uses those mobile applications to removing the disruptions of social life. The accessibility of Facebook on different mobile interfaces is evaluated by Wentz et al [14] with the help of 15 VIP. They suggested the desktop version of Facebook less accessible than a mobile interface. The uses of VizWiz mobile application is also evaluated by VIP, they classify the asked questions and used these questions as a Q&A platform for VIP.

3 Methodology

There are two phases in the experimentation. The first phase consists of, the participants were asked to use the original mobile applications as it is. At the end of user interaction with original mobile applications, user feedback, design recommendations, and user suggestions were obtained. In the next phase according to the user’s response and feedback, a new prototype of a mobile application is designed. That newly designed mobile application prototype is again evaluated by the VIP.

3.1 Participants

In this study, the target people were visually impaired and have been evaluated the usability of different mobile applications from VIP’s perspective. The VIP took part in the study with their own will. A pre-experiment interview has been taken from the participants to evaluate their level of knowledge with mobile applications. This interview helped to point out which participant can communicate and handle the mobile applications easily. On the basis of the interview, thirty-three participants were excluded out of 143. Thirteen participants found totally blind and severely visually impaired. Ten participants were facing difficulties when they interact with a touch screen mobile interface, they could not control the touch screen mobile keyboard. Six participants have no experience with the use of touch screen mobile phone applications. Finally, four participants have been refused due to their age was not between 18 and 45 years.

3.2 Materials

All participants used touch-screen mobile phones (Android) with the same android version 7.1. Audio and video demonstration of each task is given before a task is started. The study was organized in a lab. Five mobile applications used in this experiment. It was informed to all participants that if they want to quit at any stage of the experiment, or they feel that any task is more than their expectations or competency and they want to withdraw from that task then participants should quit with informed to their mentor.

  1. 1.

    Settings of any pre-installed application.

  2. 2.

    Chrome (Mobile web browser, pre-installed application).

  3. 3.

    Whatsapp (Messenger) used for mobile communication application.

  4. 4.

    Daraz (Online Shopping Portal, people use this portal for shopping ).

  5. 5.

    Facebook (Social Network Service) .

In order to better understanding the feelings particulars in this study, observed participant behavior patterns and interviewed the participants after the use of each mobile application. The participants were asked to perform each task listed below. The result of observation recorded the time consumed to complete each task and a number of successfully completed tasks. When participants declared to finish tasks then the recording is also stopped.

3.3 Tasks

Table 1. Tasks with assinged applications.
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4 VIP’s Interaction with Original Mobile Applications

All participants perform the tasks on original mobile applications. The activities performed by VIP were observed closely by a mentor. In order to make sure that VIP performed the assigned tasks by themselves and the smooth operations, the mentor was responsible for it. In order to get the reviews from VIP, post-experiment interviews were organized at the end of completing tasks. It is observed that the VIP has faced difficulties in order to perform tasks. The average time spent on an individual task by VIP and task completed by VIP is shown in Table 1.

4.1 Usability Problems in Performing the Tasks

According to the interview that was conducted after the experiment, it is concluded that VIP had the following difficulties in performing tasks on mobile applications.

4.1.1 Typing Issue

In typing 67 VIP had difficulties in typing due to layout of keypad is very concentrated. Seven VIP who said that they have well familiar with mobile keypad, they had a ten-second delay in typing also. 35 VIP had difficulty in to see the output of what they were typed.

4.1.2 Vocal Problem

In interview 48 VIP recommended that voice instructions must be included in different languages while the manufacturing of mobile applications. The usage of mobile applications is more comfortable with voice instructions for VIP.

4.1.3 Need for Assistance

There are almost 34 VIP appeal and highlighted this issue that there is a person who should collaborate them in completing their tasks.

4.1.4 Difficulties in Operation

There were 20 VIP people cannot found the Bluetooth and WiFi buttons for operating. In mobile messenger, around 34 could not found the send text image due to it has no label on that button. In order to perform the online shopping 83 VIP could not select the mobile phone for purchasing. 35 VIP could not start the voice control to place their instructions.

4.1.5 Complex Structures of Mobile Applications

There were 46 VIP people had problems on how to update their status on Facebook. 52 VIP had a problem to place a comment on their friend’s status. 36 VIP had difficulty in finding a specific friend from a list, in order to send a voice message. The bigger font size was suggested by many 25 VIP and 31 VIP had a problem in reading the text. The usability problems found in existing mobile applications by VIP, shown in Fig. 1.

Fig. 1.
figure 1

Overall percentage of Usability Problems highlighted by VIP.

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4.2 Design Recommendations

From the VIP’s feedback, the following design guidelines were collected to improve the usability of the mobile application.

  1. 1.

    The place of home and power button should be fixed.

  2. 2.

    There are proper spaces between buttons and edges of buttons are clear.

  3. 3.

    The popup/voice message of error notification should be proper.

  4. 4.

    The cursor should be blink at the entry area.

  5. 5.

    The entered character’s name must be heard.

  6. 6.

    When VIP touched an item its name should be heard.

  7. 7.

    Sound feedback can easily turn off if it is no more required.

5 Designing a New Prototype of Mobile Application

The response from VIP, about the use of the original mobile application, is a reason to design a new prototype of the mobile application. A new prototype of a mobile application was designed for the help of VIP. In the very first interaction of VIP with a new prototype of mobile application, the operating instructions will be clearly provided to operate the mobile application. A newly designed prototype was tested on Samsung A50, Huawei P10 Lite, and OPPO. This prototype will be used to enhance the usability of mobile applications for VIP, due to designing this prototype will increase the accessibility of mobile applications. Following requirements references of VIP were considered in designing the new android prototype. The adopted process in a newly designed prototype is sum up in Fig. 2.

Fig. 2.
figure 2

User-Centered Design approach for newly designed mobile application prototype.

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In the implementation of basic functionalities, a virtual keypad was taken more attention. The basic functions like add contacts, place a call, write and read messages are done with the help of a virtual keypad. In the virtual keypad, it was decided that there is a fixed number of keys and in order to utilize a mobile screen the size of keys was maximized instead of using a standard layout. In the result of VIP’s feedback, it is decided that there is a fixed place of a keypad on a mobile screen. This solution was very much impressive and fast to use. A more comprehensive analysis was compulsory in order to make voice feedback effective for VIP. In order to perform scrolling in the contact list, VIP received a very quick voice response in moving from one button to another button. It was decided to maintain the gap between two adjacent buttons. When VIP used the soft keyboard there are interesting results were obtained that VIP have difficulties in selecting the appropriate key after locating the key. In order to overcome this situation, many VIP used voice commands but this is not fruitful. The usage of vibrotactile feedback was used to overcome this problem. When VIP performed Task2 and Task5 they have difficulties after selecting a text box when they entered characters in it. There is no confirmation message that their entering character wrote into the text box or not. In order to overcome this problem in a new prototype, VIP listens to the pronunciation of those characters which are entered into the textbox.

5.1 Evaluation of New Mobile Prototype

The mobile application prototype was evaluated on the task time consumed to complete a task, performance with System Usability Scale (SUS) rating. Brooke in 1996 described that SUS is a global assessment for the usability of a system because it is a reliable and low-cost usability scale [15]. In order to create ease for usability professionals, SUS is a highly flexible and powerful tool. According to Miller and Kortum in 2008 SUS has been used for a wide range of user evaluations like mobile applications, web pages, and web applications [16]. In order to provide authentic results according to the sample size, SUS is the simplest questionnaire [17]. There are 10 questions with five response options on the Likert scale, it is chosen for this study because it has simple in structure. In a newly developed prototype, it was observed that how many time VIP take help from our team. In the results section, the comprehensive facts and figures are shown.

6 Results and Discussion

The results have shown in Table 2 are related to the original mobile applications that were installed on their mobile phones. In Task 1 104 VIP successfully completed in 45 s and 10% help was needed by VIP from our team. In Task 1 VIP had a problem to locate the position of WIFI icon. In Task 2 78 VIP have completed the task successfully and 25% help was needed by VIP from our team. In Task 2 VIP taken 678 s due to they have faced problems in finding the web browser and inserting the text in a search bar. Some VIP had used the voiceover but due to its linear nature, they also had to wait to perform their task. In Task 3 88 VIP have completed their task successfully and 17% help was needed by VIP from our team. In Task 3 VIP taken 543 s to complete the task due to they do not find both buttons like the contact list and send items buttons. In Task 4 only 2 VIP completed the task and 63% help is needed by VIP from our team. In Task 4 unlimited time was taken by VIP due to the complex structure of a web page and VIP had difficulties to select their specific item. In Task 5 46 VIP completed their task successfully and 31% help was needed by VIP from our team. In Task 5 VIP taken 894 s to complete their task due to they have problems in finding the comments of their fellow and also had a problem in confirmation of the comment which they entered in the text field.

Table 2. Time spend, number of task completion and help needed.
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The results have shown in Fig. 3 is a comparison of how much time was consumed by VIP to complete their tasks both on original and newly developed mobile prototype. In Task1 VIP consumed four minutes on an original mobile application and two minutes on a newly developed prototype. In Task2 VIP consumed nine minutes on an original mobile application and six minutes on a newly developed prototype. In Task3 VIP consumed 11 min on an original mobile application and eight minutes on a newly developed prototype. In Task4 VIP consumed 24 min on an original mobile application and 12 min on a newly developed prototype. In Task5 VIP consumed 10 min on an original mobile application and six minutes on a newly developed prototype.

Fig. 3.
figure 3

Time Consumed by VIP to Complete the Tasks.

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The results have shown in Fig. 4 are a usability percentage of tasks that are taken from the SUS questionnaire. After completing all tasks SUS questionnaire was filled in order to collect the feedback of VIP regarding usability. The usability of Task1 on an original mobile application is 63% and 93% on a newly developed prototype.The usability of Task2 on an original mobile application is 53% and 73% on a newly developed prototype. The usability of Task3 on an original mobile application is 62% and 79% on a newly developed prototype. The usability of Task4 on an original mobile application is 30% and 54% on a newly developed prototype. The usability of Task4 on an original mobile application is 46% and 87% on a newly developed prototype.

Fig. 4.
figure 4

usability percentage to Complete the Tasks.

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7 Conclusion

The usability of user-centric mobile application design with respect to visually impaired people, the main goal of this study is to provide easy access to mobile applications for VIP. This study was conducted into two phases. In the first phase, VIP use the original mobile applications from their smartphones. In this phase, VIP has faced many difficulties in using the mobile application. VIP described their experiences for a better understanding of post-experiment interviews. It was observed that VIP had difficulties in accessibility features of mobile application design, particularly when they used the virtual keyboard for typing. In the second phase, a new prototype of a mobile application was designed according to the suggestion of VIP with the help of two expert mobile application developers. This mobile application prototype again used by VIP and it was observed that there is much improvement in the usability of the newly developed mobile application prototype. In conclusion, it believed that the contribution of this study lies in producing a new effective design of mobile applications. These designs of mobile applications are referred to mobile application designers and developers, in order to develop more usable and accessible mobile applications for VIP. In order to improve the recent situation of mobile applications for VIP, there is a serious need for making international standards with the involvement of VIP.